Ignore some lines for coverage.

.coveragerc

@@ -1,4 +1,5 @@
 [report]
 # Verifier is used for testing only.
 omit =
+  */__main__.py
   */verifier.py

yapf/yapflib/reformatter.py

@@ -258,7 +258,7 @@ def __init__(self, state, newline, previous):
     self.newline = newline
     self.previous = previous
 
-  def __repr__(self):
+  def __repr__(self):  # pragma: no cover
     return 'StateNode(state=[\n{0}\n], newline={1})'.format(self.state,
                                                             self.newline)
 

yapf/yapflib/unwrapped_line.py

@@ -141,10 +141,10 @@ def AsCode(self, indent_per_depth=2):
     tokens_str = ' '.join(tok.value for tok in self._tokens)
     return indent + tokens_str
 
-  def __str__(self):
+  def __str__(self):  # pragma: no cover
     return self.AsCode()
 
-  def __repr__(self):
+  def __repr__(self):  # pragma: no cover
     tokens_repr = ','.join(['{0}({1!r})'.format(tok.name, tok.value)
                             for tok in self._tokens])
     return 'UnwrappedLine(depth={0}, tokens=[{1}])'.format(self.depth,

yapf/yapflib/yapf_api.py

@@ -148,7 +148,7 @@ def FormatCode(unformatted_source,
   return reformatted_source, True
 
 
-def _CheckPythonVersion():
+def _CheckPythonVersion():  # pragma: no cover
   errmsg = 'yapf is only supported for Python 2.7 or 3.4+'
   if sys.version_info[0] == 2:
     if sys.version_info[1] < 7:
@@ -189,7 +189,7 @@ def ReadFile(filename, logger=None):
                                       encoding=encoding) as fd:
       source = fd.read()
     return source, encoding
-  except IOError as err:
+  except IOError as err:  # pragma: no cover
     if logger:
       logger(err)
     raise